Process for the manufacture of asphalt



Patented Nov. 29, 1932 UNITED STATES PATENT oFFIcE ALBERT LoEBEL, OFAMSTERDAM, NETHERLANDS, Assienon To NAAMLOOZE vENivooT- scHAr DEBAT'AAFSCHE PETROLEUM MAATSOHAPPIJ, ,OF THE. HAGUE, NETHER- LANDSPROCESS FOR- THE MANUFACTURE OF ASPHALT No Drawing. Application filedApril 19, 1930, Serial No. 445,818, and. in the Netherlands December 9,1927.

It is known that crude asphaltic oil, after any gasolene, kerosene andgasoil contained therein have been removed by distillation, yields onfurther distillation a residue which, depending on the extent to whichthe distillation is carried out, represents a more or less hard asphalt.

For practical purposes, asphalt should comply with various requirementswhich differ according to the purpose for which it is used. From adefinite crude oil, only one and the same quality of asphalt may beobtained by distillation, which can only be modified slightly byaltering the conditions under which the distillation takes place.

Also, With the aid of oxidizing treatments (the well-known blowing ofasphalt), it is only possible to alter the quality of the asphaltgradually.

I have found, however, that the quality of the final product to beobtained from an oil may be highly improved by adding thereto, at anystage of the distillation (if desired, even to the starting material, i.e., the crude oil), a hydrocarbon oil containing at least 20% ofhydrocarbons which can be easily sulphonated and have a relatively highboiling point ,(above 250 C.). The added material is prepared bytreating. a hydrocarbon oil according to the normal method of Edeleanuwith liquid sulphur dioxide. By this treatment the higher unsaturatedconstituents mostly, though not quite correctly called aromaticsareremoved. These removed higher unsaturated constituents aresulphonifiable hydrocarbons soluble in liquid sulphur dioxide.

If, according to my invention, an oil to which the said material isadded is subjected to a distillation with steam, at a temperaturepreferably above 340 0., a final product is obtained which, incomparison with the product obtained from the same oil and under thesame circumstances but without the addition of a material containing atleast 20% of hydrocarbons which are sulfonifiable but insoluble inliquid S0 is very resistant against changes in temperature. Thus, if anoil yields normally, by distillation, a final product of insufficientresistance against changes in temperature, I may add to such oil,according to my invention, the said material and then subject themixture to a distillation with steam, preferably above 340 C.

From the following table, relating to such distillation of a mixture ofVenezuelan residue and the said material, in comparison with adistillation of that residue without admixture, those skilled in the artwill be able to ascertain the technical eflect obtained according to myinvention.

Steam asphalt The invention, as herein described and claimed, is acontinuation in part of that disclosed in my prior application No.340,006, filed February 14, 1929.

What I claim is: v

1. A process of manufacturing asphalt from crude asphaltic oil orasphaltic residuum, comprising the steps of extracting a hydrocarbon oilhaving an initial boiling point of at least 250 C. with liquid sulphurdioxide, then adding to the asphaltic oil or residuum that portion ofthe hydrocarbon oil subjected to the extraction treatment which isinsoluble in the liquid sulphur dioxide, and blowing the mixture to forman oxidized asphalt.

2. A process of manufacturing asphalt from crude asphaltic oil orasphaltic residuum, comprising the steps of extracting a hydrocarbon oilhavingan initial boiling point of at least 250 C. with liquid sulphurdioxide, then adding to the asphaltic oil or residuum that portion ofthe hydrocarbon oil subjected to the extraction treatment which isinsoluble in the liquid sulphur dioxide, and subjecting the mixture tosteam distillation at a temperature above 340 C. to produce an asphaltresistant to temperature changes.

In testimony whereof I affix my signature.

ALBERT LOEBEL.

